Use of amblygonite as an additive in the lime-roasting of lithium-aluminosilicate ores



o United States Patent ce Patented Jan. 1, 1957 TABLEII 2s776201 [Results from 60-40 tests] USE OF AMBLYGONITE AS AN ADDITIVE IN THE LIME-ROASTHVG OF LITHIUM-ALUMINOSILI- Test CATE ORES I 11 III IV Harold Mazza, Stanley L. Cohen, and Glen H. Schafer,

Trona, Calitl, assignors to American Potash & Chemical Corporation, a corporation of Delaware ttilliifi iihfff i312? podumene, grams 21. 42 21.42 No a November 15,1955, taste: sass ran as fi fiiiitfit fih i a 3*? 4 Claims. (Cl- 75-1) Q0: content of clifiielfiiffifi 6.1 5:9 as 6:0 ililhlfiitliflg'iafih fif all; 562 o 1bl 0 8bl This invention relates to recovery of lithium from the u I g gg 'g fh itg j spodumege f fi a t l l n Example 2.-A series of roasts was made using mixb n esedl can emas e i tures of approximately 90% petalite and 10% ambly- 81 1312? Ten cortent water 1 gonite and mixtures of approximately 90% spodumene 2 1um s f fi f fi extract: n i and 10% amblygonite. The methods of roasting and i e roastmg 0 t 656 ores necessary to use re leaching the charges were identical to those given in Exg i 132 253 6??? temperatures of the order ample l. The results obtained are tabulated below:

We have found that these lithium ores can be success- TABLE III fully roasted with calcium carbonate, at a significantly [Results from 90-10 tests.] lower temperature and to economic advantage if amblygonite is present as a constituent in the roast. Apparently, 'lest N0. the fluxing constituents in the amblygonite are such that they enable the lithium values to be extracted from such I II III IV ores when these are first roasted with calcium carbonate at temperatures of the order of 800 to 950 C. It has Am lygonite, grams 3.24 3.2-1 3. 57 3.57 heretofore been necessary to heat spodumene and petalite 5,23%;55325 29'16 16 ""551;- ""55 to temperatures of the order of 1000-1200 C. to change Limestone, grams 117i 6 117. 6 114.3 114. 3 their mineral form to one upon which subsequently limegggiiggfflfi 3' 361 roasting could be successfully pract1ced. Thus, the pres- Rt me, ou s 2 2.5 2 2. 5 ence of amblygonite in the roast obviatesthe heating to 35 g ;fgg igg g iy gikggfif: 23 13 2:; 21, a high temperature of spodumene or petahte and enables Aluminainleach quor 0i004 0. 004 0. 004 0.004 the lime-roast to be carried out at a much lower temperature. From Tables 11 and III, it will be apparent that a Typ1cal analyses of amblygomte and ot the lith um marked improvement in lithium recovery can be obtained alumlnosihcate ores, spodumene and petahte, are glven 40 when lime-roasting petalite or spodumene at 900 C. by in Table I. adding a small quantity of amblygonite to the roast mix- TABLEI ture. The quantity of amblygonite can be as low as approximately 10% of the weight of the total lithium ore Percent treated. The amblygonite content of the charge can be Ore increased until 'amblygonite provides substantially the L120 K sio F 5 only lithium source but, as we have indicated, the temperature of the roast can be reduced to 900 C. when as Amblygonite 9.14 6.62 33.0 5.46 44,02 little as 10% is present. The utilization of a larger quani thitifjjjiiiiii 2:22 8133 9% iii 2832 $7383 my Of tmblygmite, 40%, makes it Pwible to prov1de a very economlcal process for the recovery of lithium values at relatively low roast temperatures. The practlce of the prfasent .mventlon W111 9 Spodumene and petalite mixtures can also be roasted ther apparent upon consideration of the following.

successfully by addmg amblygomte to such a mixture. Example 1.-A senes of roasts were made usmg (1) The limestone to mixed or afio t be b d h mixtures containing approximately 60% petalite and 40% ff b1 i 1 f rings on t e amblygonite and (2) mixtures containing approximately 6 ,11; or 1 y :2 ca mum car .onate P spodumene and 40% amblygonite. The limestoneen fi S correct 6 actual q.u.antlty of to-ore ratio on a weight basis was 3.63 to 1 for the petalitestone y ta "9. account the ,quantltles Prfa'sent of amblygonite mixtures, and 32 to 1 for the spodumene magnes um ox de, silica, and alumma. Magneswm caramblygonite mixtures; these ratios were such as to main- 60 1 1S efiectlve a for calcium carbonate P tain a constant calcium to sflica ratio in the charge The a l1m1ted extent. Those skilled 1n the oreroasting art w ll individual charges were roasted in stainless steel crucibles f dlfiiculty m selectulg good m in a laboratory muffle furnace under the conditions shown amvmg at the P P q y of the natural llmeStOne in the following table. The resulting clinkers were each Selectei quenched in one liter of hot water and then leached with We clalmr agitation and at boiling under reflux for sixteen hours. The results obtained are tabulated below:

1. In a lime-roast process for recovering lithium, the step comprising roasting a finely divided mixture of calcium carbonate, amblygonite and an ore selected from the group consisting of spodumene, petalite, and mixtures thereof, at a temperature of from about 800 C. to about 950 C., the amblygonite providing at least approximately 10% of the total weight of the lithium ore mixture.

2. In a lime-roast process for recovering lithium, the step comprising roasting a finely divided mixture of calcium carbonate, amblygonite and an ore selected from the group consisting of spodumene, petalite, and mixtures thereof, at a temperature of from about 800 C. to about 950 C., the amblygonite providing at least approximately 40% of the total weight of the lithium ore mixture.

3. In a lime-roast process for recovering lithium, the step comprising roasting a finely divided mixture of calcium carbonate, amblygonite and an ore selected from the lithium-aluminosilicate group consisting of spodumene and petalite, and mixtures thereof, at a temperature of from about 800 C. to about 950 C., the amblygonite providing at least approximately 10% of the total weight of the lithium o're mixture, the available calcium carbonate to amblygonite and ore ratio being between three and four to one.

4. In a lime-roast process for recovering lithium, the step comprising roasting a finely divided mixture of calcium carbonate, amblygonite and an ore selected from the lithium-aluminosilicate group consisting of spodumene and petalite, and mixtures thereof, at a temperature of from about 800 C. to about 950 C., the amblygonite providing at least approximately 40% of the total weight of the lithium ore mixture, the available calcium carbonate to amblygonite and ore ratio being between three and four to one.

References Cited in the file of this patent UNITED STATES PATENTS 

1. IN A LIME-ROAST PROCESS FOR RECOVERING LITHIUM, THE STEP COMPRISING ROASTING A FINELY DIVIDED MIXTURE OF CALCIUM CARBONATE, AMBLYGONITE AND AN ORE SELECTED FROM THE GROUP CONSISSTING OF SPODMENE,, PETALITE, AND MIXTURES THEREOF, AT A TEMPERATURE OF FROM ABOUT 800* C. TO ABOUT 950* C., THE AMBLYGONITE PROVIDING AT LEAST APPROXIMATELY 10% OF THE TOTAL WEIGHT OF THE LITHIUM ORE MIXTURE. 